9307-P pico-TIMING Discriminator

The Model 9307-P pico-TIMING Discriminator defines the arrival time of analog pulses from ultra-fast detectors with picosecond precision. Moreover, this superb performance is delivered over an extremely wide range of pulse heights with negligible influence of pulse
amplitude on the timing output. With the Model 9307-P, the difficult task of adjusting pulse-shaping cables has been eliminated. The internal pulse shaping in the pico-TIMING Discriminator is optimum for single-photon or single-ion time measurements with microchannel plate detectors, microchannel plate photomultiplier tubes (PMTs), channeltrons, fast photomultiplier tubes, and fast silicon photodiodes.

The pico-TIMING Discriminator accepts analog input pulses with amplitudes ranging from
-50 mV to -5 V, and pulse widths from 400 ps to 5 ns FWHM. The amplitude threshold for generating a timing output is adjustable from -25 mV to -1 V with a 10-turn locking dial.

Ultra-fast circuits are incorporated in the pico-TIMING Discriminator to minimize time slewing. As a result, input amplitudes can vary over as much as a 100:1 range with negligible shift in the timing output. This ensures excellent time resolution, even when the signal source produces a wide range of randomly varying signal amplitudes. A front-panel screwdriver adjustment permits fine-tuning the slewing compensation to match the characteristics of a particular detector. An adjacent test point makes it easy to monitor the adjustment with a voltmeter.

Two fast negative NIM outputs provide the flexibility to trigger a time-to-amplitude converter (TAC) while simultaneously driving other instruments. The 500-ns-wide TTL output can be used with instruments that require a positive logic signal, such as counters and ratemeters. A front-panel LED flashes with each output pulse to indicate triggering.

For detectors having rise times less than 1 ns, the Model 9306-P 1-GHz Preamplifier should be used to amplify small signals before presentation to the input of the Model 9307-P plco-TIMING Discriminator. For rise times ≥1 ns, the Model VT120-P Fast-Timing Preamplifier should be substituted for the Model 9306-P.The Model 9307-P incorporates a compatible, 9-pin 0 connector on its rear panel to supply power to either preamplifier.

Front-panel, 20-turn, screwdriver fine-tuning to minimize time slewing as a function of input pulse amplitude. Adjustment over a range of approximately ±30 mv. A front-panel test point located next to the potentiomenter facilitates monitoring the actual setting. Test point output impedance: 100 Ω.

OUTPUT LED

Front-panel LED flashed on each output pulse to indicate active triggering.

Rear-panel, 9-pin D connector provides ±12-V and ±24-V power for the Model 9306-P 1-GHz Preamplifier, the Model VT120-P Fast-Timing Preamplifier, or other preamplifiers utilizing the industry-standard premamplifier power plug.

ELECTRICAL AND MECHANICAL

POWER REQUIRED

The Model 9307-P derives its power from a NIM bin/power supply, such as the Model 4001A/4002D. Required dc voltages and currents are: +12 V at 35 mA, +6 V at 70 mA, -6 V at 360 mA, and -12 V at 100 mA.

The Model 9306-P 1-GHz Preamplifier is recommended for amplifying ultra-fast analog signals before presentation to the input of the Model 9307-P pico-TIMING Discriminator. These ultra-fast analog signals require the use of 50-Ω coaxial cable with SMA connectors. To preserve the 350-ps rise time of the 9306-P, the total cable length from the detector to the preamplifier, and from the preamplifier to the 9307-P should be <1.7 m. Consult the ordering information for the appropriate SMA cables and adapters. For detectors having rise times >1 ns, the Model VT120-P Fast-Timing Preamplifier should be substituted for the Model 9306-P. In that case, 50-Ω coaxial cables with BNC connectors can be used. Consult the list below for BNC to SMA adapters, and refer to the Cables and Accessories data sheet for the desired cables.